Squeeze chutes are well known and conventionally include a generally channel shaped frame structure having a head end for receiving a head of an animal to be confined, two sides each for extending along a respective side of the animal to be confined, a tail end remote from the head end. A head gate assembly at the head end is operable to move from a release position to a closed position in which the neck of the animal is grasped for confinement of the animal. In some cases, a squeeze side panel is arranged along one side and is operable in a pivoting action to squeeze the animal from one side onto the other side panel so that the body of the animal is also confined. A tail gate section is often provided at the rear end to close behind the animal as it enters the squeeze chute.
The head gate typically comprises a pair of parallel vertical bars with a spacing between them sufficient to receive the neck of the animal without damage but insufficient for the head to be pulled out of the bars and insufficient for the animal to move forward. Each of the bars forms part of a frame which pivots about a vertical axis parallel to the bar and spaced outwardly of the bar. In the locked holding position the frame and the bars line in a common plane transverse to the chute with the bars at their point of closes approach. In a set portion the bar pivots so that it moves along the chute toward the incoming animal with the frame inclined out of the common plane thus increasing the space between the bars.
Thus to catch the cattle by the head, it is common to have a head gate that locks by itself as the cattle try to walk through it. When set in the set catch position, the bars are turned toward the approaching cattle. The approaching animal will see an opening sufficient for its head and try to walk through. The head will fit through the opening, but as the animal tries to walk forward its shoulders hit the bars and the bars move forward with the shoulders until the bars hit a latch at a top of the head gate locking them in the catch position in which the bars lie in the common plane. Normally head gates have a handle projecting out of the frame of one of the bars to one side of the chute which allows a worker standing to that side to push the handle to pivot the frame about its vertical axis that helps pivot head gate to be closed.
Head gates have been manufactured in this construction for many years and many manufacturers have arrangements which operate effectively in this manner. It will be appreciated that the animals concerned are very large and strong with great ability to do damage to themselves and the worker. It is thus highly desirable that even highly recalcitrant animals are trapped in the head gate as quickly and simply as possible with little possibility to back up before being trapped.